PhD PROPOSAL FOR THE PASTEUR-PARIS UNIVERSITY INTERNATIONAL PROGRAM

 

Deadline for full application: December 15th, 2013

Interviews: March, 2014

Start of the Ph.D.: October 1st, 2014

 

 

Department: Department of Neuroscience

Title of the PhD project: Development of novel super-resolution microscopy methods for quantitative dynamic neuronal imaging

Name of the lab: Unit of Dynamic Neuronal Imaging

Head of the lab: David DiGregorio

PhD advisor: Gael Moneron

Email address: david.digregorio@pasteur.fr, gael.moneron@pasteur.fr

Web site address of the lab:

Doctoral school affiliation and University:

 

 

 

Presentation of the laboratory and its research topics:

 

The Unit of Dynamic Neuronal Imaging specializes on the development and application of optical methods for the study of information processing in cerebellar and cortical circuits. Biological projects in the laboratory involve electrophysiological recordings in acute slices from wild type and transgenic animals, biophysical analysis, and numerical simulations.

Imaging modalities include rapid single and multi-photon imaging of intracellular calcium and membrane voltage, as well as photo-uncaging of neurotransmitter.

In parallel to the biological projects, research in optics is conducted on novel microscopy methods mainly focused on super-resolution techniques (e.g. STED microscopy) and aims at developing and implementing the state-of-the-art of microscopy for the needs of the neurobiological projects.

 

 

Description of the project:

 

Far field fluorescence microscopy is a method of choice for complementing electrophysiology in the exploration of the dynamics of interactions between the different signaling molecules involved in the synaptic activity, owing to its relative non-invasiveness, its high molecular specificity, and the availability of fluorescent indicators capable of reporting submillisecond changes in neuronal signaling.

Conventional diffraction-limited fluorescence imaging tools (e.g. confocal or 2-photon imaging) provide sub-micron resolution enabling the ability to monitor activity at single synapses. However the nanoscopic dynamics within the synapse (< 200nm) remain inaccessible with these methods. A classic example, and a subject of great interest in the laboratory, is the study of [Ca2+] gradients driving synaptic transmission: they are steep and localized to 10’S to 100’s of nanometers within the presynaptic terminal, well below the diffraction limit of conventional fluorescence microscopy. In order to surpass the limits of the above mentioned methods, and to probe the molecular players influencing nano-signalling at synapses, we propose to merge novel sub-diffraction imaging techniques with the neurobiology and biophysics expertise to examine nanoscopic signals occurring within single synapses.

The candidate will work on the development of novel optical methods with sub-diffraction spatial resolution (a few tens of nanometers) and high-temporal resolution (a few microseconds), and adapt them for use with electrophysiology for neurophysiology experiments. The optical methods will mainly be based on stimulated emission depletion (STED) microscopy with two-photon excitation and multi-parameter acquisition. The candidate is expected to model, develop, implement and apply the new methods in collaboration with the other members of the group in a unique environment where all the skills are present within the same laboratory.

 

 

 

References:

 

G. Moneron, and S.W. Hell, “Two-photon excitation STED microscopy,” Optics Express, vol. 17, p. 14567-14573 (2009).

 

G. Vicidomini, G. Moneron, K.Y. Han, V. Westphal, H. Ta, M. Reuss, J. Engelhardt, C. Eggeling, and S.W. Hell, “Sharper low-power STED nanoscopy by time gating,” Nat. Methods, vol 8,p. 571-573 (2011).

 

Keywords:

 

Super-resolution Microscopy, Imaging, Nanoscopy, Optics, Biophysics, Neurobiology

 

 

Expected profile of the candidate (optional):

 

 

Contact:

 

Gael Moneron (gael.moneron@pasteur.fr), David DiGregorio (david.digregorio@pasteur.fr)

Mis à jour le 16/09/2013